This invention relates to a sheet feeder used in an electrostatic recording apparatus such as an electrophotographic copier and particularly to a sheet feeder having a sheet feeding member for transporting sheets and a sheet peeling member that is brought into pressure contact with the sheet feeding member so that double-feeding of sheets can be prevented.
Recently, there has been used, in high-speed type electrophotographic copiers and the like, a sheet feeder having a sheet feeding member such as a sheet feed roller for taking sheets out of a sheet cassette and a means for preventing double-feeding, or a sheet peeling member that is brought into pressure contact with the surface of the sheet feeding member so that the double-feeding of sheets can be prevented.
In this type of sheet feeders as described in U.S. Pat. No. 3,768,803, a plurality of sheets are taken out of a sheet cassette by driving the sheet feeding member and the uppermost sheet is supplied one after another by the action of the sheet peeling member. In the sheet feeder constructed as mentioned above, since several sheets remain sandwiched between the sheet feeding member and the sheet peeling member even in a non-sheet-feeding state, those sheets are sometimes left inside the copier when the sheet cassette is detached from a sheet feeding table.